Methods: A total of 232 patients who were received in department of cardiology were involved in this study. Genotype frequencies of the first two groups were investigated and compared. After determination of ACE I/D polymorphism, all patients were further divided into new three groups as the II homozygotes, ID heterozygotes, and DD homozygotes to investigate relationship ACE I/D polymorphism and other risk factors of SCA. Statistical analysis was used to analyse the data.

Results: Frequencies of DD genotype in SCA group was higher than the coronary disease group, P<0.05, and the D allele frequencies in SCA group compared with coronary disease group, P<0.05. Results of distribution of patients’ characteristics according to the genotypes of the ACE I/D polymorphism showed no significant differences among all characteristics except for percentage of patients survival after SCA in which patients with II genotype had significant higher percentage, P<0.05, and patients died of SCA in which DD genotype had significant higher percentage, P<0.05.

Conclusion: The DD genotype is associated with a higher prevalence of SCA and may be a risk factor of survival rate of sudden cardiac death.